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In this study, we sought to identify efficient enzymes for use in monitoring the deterioration and loss of germination of Balfourodendron riedelianum (Engler) Engler seeds. The research was conducted at the Laboratório de Tecnologia de Sementes e Mudas of the Universidade Estadual do Oeste do Paraná, Campus Marechal Cândido Rondon, Paraná State, Brazil. Seeds were harvested at three collection sites and later submitted for processing, drying, initial characterization and storage in airtight packaging under controlled and uncontrolled storage conditions and uncontrolled. Tests were conducted at 0, 120, 240, and 360 days using a germination test, germination speed index, accelerated ageing test and the activity of peroxidase, phenylalanine ammonia-lyase and β-1,3-glucanase. The experiment was a completely randomized design. The results were subjected to regression analysis at 5% probability. Ageing was different among sample sites and between different storage conditions. The decrease in viability of seeds of Balfourodendron riedelianum (Engler) Engler was detected based on the activity of peroxidase enzymes in seeds from the Diamante do Oeste and Missal sites and the enzyme β-1,3-glucanase in seeds from the Missal site after storage periods of 0, 120, and 240 days.

Among the many species that can be used to obtain vegetable oil for energy, Jatropha is considered one of the best options. Therefore, it is necessary to have seeds with good physiological and health quality in order to have a good establishment of plants in the field. This study aimed to evaluate the efficiency of heat treatment to the control of seed-borne pathogens in stored Jatropha seeds. The experimental design was completely randomized with a factorial 5x4 (five periods of storage x four treatment temperatures). The seeds of Jatropha were collected in Dourados - MS, and were subjected to processing and sun drying, and then stored in a dry chamber in glass flaskswith a screw cap and a capacity of 500 mL, for periods of 0, 90, 180, 270, and 360 days. After each storage period, seeds were subjected to thermotherapy by immersion in hot water at temperatures of 45°C, 50°C, and 55°C for 15 minutes; the control treatment was immersed in water at room temperature (25±2°C) for 15 minutes. The parameters evaluated were: moisture content, germinations, germination speed index, electrical conductivity and health. Heat treatment at temperatures of 45°C, 50°C and 55°C don’t affect germination and the cell membrane integrity of the seed. After 180 days the use of thermotherapy contributed to the conservation of seed vigor. The fungus Penicillium sp. and Acremonium sp. are eliminated by thermotherapy at temperatures of 45°C, 50°C and 55°C, and Aspergillus sp. is controlled at a temperature of 55°C in periods of storage of 180 and 270 days.

This study aimed to identify damages caused by stink bugs in seeds of physic nut through the tetrazolium test. Seeds were soaked in water for 16 hours. After tegument removal, the albumens were submerged in tetrazolium solution at concentration of 0.5% for 4 hours at 40 ± 2 °C in BOD without light, and evaluated according to the levels of viability and damages by stink bugs. The tetrazolium test was efficient to evaluate the viability of physic nut seeds allowing the interpretation of vigor and damage caused by insects.